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M. R. MOORE;

I REVERSING VALVE GEAR. No. 308,917. Pat d Dec. 9, 1884.

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MATTHE\V 1t. MOORE, OF INDIANAPOLIS, INDIANA.

REVERSING VALVE GEAR.

Application tiled July 20, 15953.

To all whom it may concern:

Be it known that I, Mirr'rninw It. Moons, of the city of Indianapolis,in the county of Marion and State of Indiana, have invented a new anduseful Improvement in Reversing Valve-Gears for Steam-Engines, for whichI wish to obtain Letters Patent of the United States; and I do herebydeclare that the following specification is such a full, clear,andcomplete description of the same as will enable any person skilled inthe art to which it pertains to understand and construct the same,reference being had to the drawings hereto at tached, and forming partof this specification, and to the letters of reference marked thereon.

The object of m y invention is to provide a more simple, cheap, andconvenient valvegear than any now in use,whereby the motion of asteam-engine may be reversed, so that the engine-shaft may be made torevolve forward or backward at the will of the engineer.

My improvement relates to that class of reversing valve-gears whereinthe eccentric which gives motion to the valve is not iixed upon theengine-shaft, but has a slotted hole for the shaft to extend through, sothat,being in the proper position to give motion in one direction, theeccentric may be slipped across the shaft into another position properfor giving motion in the opposite direction; and it consists inproviding-asimple, convenient, and eflicient mechanism for so slippingthe co centric from one position to the other, and holding the same inplace while the engine may be in motion. The arrangement is such that itmay also be used as a variable expansion-gear, the lead givenv to thevalve remain ing constant in all positions for both forward and backwardmotions.

The accompanying drawings form a part of this specification, andrepresent what I con sider the best means of carrying out the invention.

Figure 1 is a perspective view. Fig. 2 is a side view of the eccentricdetached.

Similar letters of reference indicate like parts in both figures wherethey occur.

Referring to the drawings, the construction and operation of the devicemay be understood from the following description.

Fig. 1 represents a portion of the engine shaft A with the eccentric andreversing-gear IFZC'ATIGN forming part of Letters Patent No.

308,917, dated December 9, 188 1.

(No n cd 1.)

upon it. The eccentric I3 is not fastened directly to the shaft, whichextends through a slotted opening therein, but without touching.

G is a collar surrounding and bolted to the shaft, havingtwoprojectingguide-arms which slide in guideways b, formed on the eccentricB, back and forth. The collar 0 also bears a stud, 0, upon which turns asmall cog-wheel or pinion, D, which gears with a rack, E, fixed upon theeccentric, and also with another rack, F, borne by an arm, G, projectingfrom a sliding collar. This collar G is set upon a feather, whichcompels it to revolve with the shaft; but it may be shiftedlongitudinally or held in any position within its traverse by means ofthe clutch-fork H, the handle of which is pivoted to a bracket, I,projecting from the engine-frame I, and extends, further,

to any convenient point, (not represented) where it may be provided withthe notched sector and detent usually employed to fix the position ofreversing-levers.

The eccentric is so proportioned and is secured to the shaft by means ofthe fixed collar C in such a way that when in the position shown in Fig.ltl1at is, slid out to one side as far as its slotted hole willpermit-it will give the valve the proper motion to drive the engine inone direction, cutting ofi the steam at about three-quarters stroke. Theposition of the slotted hole and gib-arms is such that when theeccentric is at the middle of its traverse, as shown in Fig. 2, or asnearly concentric with the shaft as it can come, it will still havethrow enough to move the valve through a space equal to twice its lapand lead, and this throw will be exactly op posito that of the enginescrank if the valve be directly connected, or will coincide with thecrank if the valve-motion be reversed by a rock-shaft. \Vhen theeccentric is carried to the opposite limit of its traverse,it will havethe right position with reference to the crank to give the valve-motionrequired to drive the engine in the reverse direction. It will now bereadily seen how by working the handle II the eccentric may be traversedfrom one side to the other, thus reversing the motion of the enginealso,that since the angular advance of the eccentric increases inproportion as its throw diminishes as it approaches the middle of itstraverse, the valve will be caused to cut off the steam earlier, whileits lead will re- 1 trio.

main constant. The arrangement thus becomes as efficient a variableexpansion valvegear as is possible with a single valve.

Some important advantages are possessed by this device over otherarrangements in conmon use for effecting the same purpose. There are noparts of this reversing-gear subjected to wear while the engine isrunning, other than those common to a non-reversing engine with fixedeccentric. As compared with the link-motion, which is most generally inuse,it has fewer parts, no pins nor sliding blocks subject to wear, andgives a more correct valve action. As compared with other patenteddevices for shifting the eccentric, it is simpler, more compact andpositive, and being arranged entirely upon one side of the eccentricmakes it possible to bring thelatter close to the main bearing of theengine and get as direct a connection with the valve as with theordinary non-reversing fixed eccen- This device is of course asapplicable to air or gas as to steam engines. I

I am aware of Patent No. 231,834, of 1880, and the construction thereinset forth is not sought to be covered in this application.

WVhat I claim is- In a reversing valve-gear for steam and analogousengines,'the combination, with the shaft A and frame I I, of the collar0, secured to the shaft, and having guide-arms 0* and stud O, theeccentric B, having guideways b and rack E, the collar G, havingprojecting arm G,supporting rack F, and having feather- 35 connectionwith the shaft,and the lever H, all arranged and operating as and forthe purposes set forth.

Indianapolis, Indiana, July 12, 1883.

MATTHEW R. MOORE.

\Vitnesses:

H. H. HANNA, FRANK F. VATER.

